What to know about the cleanse programs that are sweeping the nation.

Ingredients: Shakes plus chef-prepared "clean food" meals.Celebrity Users: Justin Timberlake, Kate HudsonPerks: Involves more gourmet meals than detox shakes.Cost/Duration: $645/10 daysRant: "I will not do this cleanse again. The food was one step above bad."**Rave: "I just wish I could afford to do this longer than the two months I planned."**